Macraeite is the fourth type mineral to be described from the Mangualde pegmatite, Portugal, and is the first paulkerrite-group mineral to be characterised from the locality. Its crystal structure has been refined using synchrotron diffraction data, and its chemical analysis, Raman spectrum, and optical properties are reported.

Regerite is the first new mineral species to be described from the Kreuzberg pegmatite, Pleystein, in the Oberpfalz, Bavaria. It has been characterised using electron microprobe analysis, Raman spectroscopy, optical measurements and a synchrotron-based single-crystal structure refinement. The structure type for regerite has not been previously reported.

Hochleitnerite is a new member of the paulkerrite group of minerals. Its crystal structure, chemical analyses and Raman spectroscopy are reported, and its crystallochemical properties are discussed in relation to other group members.

Manganrockbridgeite, Mn²⁺₂Fe³⁺₃(PO₄)₃(OH)₄(H₂O), a new member of the rockbridgeite group, has been characterised using electron microprobe analyses, Mössbauer spectroscopy, optical properties and single-crystal X-ray diffraction. Whereas other rockbridgeite-group minerals have orthorhombic symmetry with a statistical distribution of 50%Fe³⁺/50% vacancies in M3-site octahedra, monoclinic manganrockbridgeite has full ordering of Fe³⁺ and vacancies in alternate M3 sites along the 5.2 Å axis.

Pleysteinite has been approved as a new mineral species, and we describe here the characterisation of the mineral and its relationship to related minerals benyacarite, paulkerrite and mantienneite. The characterisation includes the determination and refinement of the crystal structure, electron microprobe analyses, optical properties and interpretation of its Raman spectrum.

The paper gives a characterisation of the new mineral species, whiteite-(CaMnFe), which has recently been approved as a new mineral (proposal IMA2022-077). The study included a single-crystal structure refinement that, when combined with electron microprobe analyses, confirmed that the mineral was a new member of the whiteite subgroup of the jahnsite group of minerals. Relationships between the crystal structure and the unit-cell parameters for the whiteite-subgroup minerals are discussed.

This paper describes the characterisation of a new mineral from a South Australian phosphate quarry. The characterisation included chemical analyses, infrared spectroscopy, and a determination and refinement of the crystal structure. The results showed that the mineral has a unique crystal chemistry, but it is closely related to the well-known phosphate mineral crandallite.

A reinvestigation of angastonite from the type locality has shown that it is a mixture of crystalline phases and an amorphous phase, with the published formula corresponding to the amorphous phase. A redefinition proposal for angastonite as an amorphous mineral was approved by the IMA CNMNC. Our study showed how the amorphous phase formed and how it progressively recrystallises as new crandallite-related minerals.